AIM: To study the dynamic levels of tumor necrosis factor alpha (TNF-?), interleukin-6 (IL-6) and gamma interferon (IFN-?) produced by human dendritic cells infected with Dengue virus. METHODS: Monocytes isolated from healthy human peripheral blood were incubated in medium with GM-CSF and IL-4 for more than 7 days. DCs were then collected and identified by scanning electron microscope, immunohistochemistry and lymphocytes stimulatory ability. Human dendritic cells (DC) were infected with Dengue-2 virus (DV-2) in vitro, culture supernatants were collected in different time postinfection (6 h, 12 h, 24 h, 48 h and 72 h), DV antigen in human dendritic cells were demonstrated by an indirect immunofluorescent assay (IFA), production of TNF-?, IL-6 and IFN-? in the culture supernatants were evaluated by ELISA. RESULTS: After 7 days, typical dendritic cells could be obtained. Virus antigen were detected in infected DC by IFA. Dengue virus induces TNF-? and IL-6 secretion from DC and does not induce IFN secretion. CONCLUSION: Human dendritic cells are target of dengue virus infection. TNF-?, IL-6 production from DC are increased with DV infection. Dendritic cells may play an important role in DV pathogenicity and immunity.

Objective:To explor the effect of gp120mAb on synaptic transmission and plasticity changed by gp120 in the CA 1 region of rat hippocampal slices.Methods:We recorded the excitatory postsynaptic potentials (EPSP) and investigated effect of gp120mAb on long-term potentiation inhibited by gp120 in rat hippocampus in vitro.Results:The results showed that HIV-1 gp120 can inhibit the LTP induced by high-frequence stimulation schaffer in CA 1,gp120 had no effect on basal synaptic transmission.HIV-1 gp120(200 pmol/L) can inhibit the LTP maintance,gp120mAb of gp120-specific antibodies can reverse the inhibition effect,But IgG can't reverse it.Conclusion:The reverse effect of gp120-specific antibody gp120mAb on long-term potentiation inhibited by HIV-1 gp120 may contribute to the HAD pathogenesis.

AIM:To evaluate the ability of dendritic cells (DCs) loaded with tumor lysate to initiate cell mediated immune responses by stimulating naive T cells, and the efficiency of activated T cells to kill autologous tumor cells in vitro. METHODS: The peripheral blood lymphocytes and monocytes were obtained from the advanced renal cell carcinoma patient by eonglutination method. The immature dendritic cells were generated in the presence of interleukin -4(IL-4) and granulocyte/macrophage colony-stimulating factor (GM-CSF) from monocytes of healthy individuals.These cells were pulsed with tumor lysate or not. Induction of tumor-specific cytotoxic T lymphocytes(CTLs) response by mature dendritic cells (mDCs) was evaluated by the CD95(Fas) expression assay through FCM and the cytotoxic assay a gninst autolognns human tumor cells. RESULTS: Human immature dendritic cells and T cells obtained from healthy donors were stimulated with tumor- pulsed dendritic cells. The immature dendritic cells were applied to the cytotoxicity assay a gainst target autologons tumor cells. The CD95 (Fas) expression, IFN-γ, and TNF -α secreted by the CTLs in tumor lysate-plused DC group were higher than those of other groups. The capacity of the CTLs to kill autolognns tumor cells was significantly different(P<0. 05). Antigen-specific DCs vaccine can induce T cells activation and proliferation, thus we can obtain higher proportion of tumor specific cytotoxic T cells(CTLs), and enhance the CTLs to secret IFN-γ and TNF-α. CONCLUSION: Our results indicate that monocyte-derived human dendritic cells pulsed with tumor lysate could in duce the specific antitumor effect against autologons tumors. This in vitro model offers a new and simple approach to the development of DC + CTL - based immunotherapy.

AIM:To evaluate the ability of dendritic cells (DCs) loaded with tumor lysate to initiate cell-mediated immune responses by stimulating naive T cells, and the efficiency of activated T cells to kill autologous tumor cells in vitro. METHODS: The peripheral blood lymphocytes and monocytes were obtained from the advanced renal cell carcinoma patient by conglutination method. The immature dendritic cells were generated in the presence of interleukin-4(IL-4) and granulocyte/macrophage colony-stimulating factor(GM-CSF) from monocytes of healthy individuals. These cells were pulsed with tumor lysate or not. Induction of tumor-specific cytotoxic T lymphocytes (CTLs) response by mature dendritic cells (mDCs) was evaluated by the CD95(Fas) expression assay through FCM and the cytotoxic assay against autologous human tumor cells. RESULTS: Human immature dendritic cells and T cells obtained from healthy donors were stimulated with tumor-pulsed dendritic cells. The immature dendritic cells were applied to the cytotoxicity assay against target autologous tumor cells. The CD95(Fas) expression, IFN-? and TNF-? secreted by the CTLs in tumor lysate-plused DC group were higher than those of other groups. The capacity of the CTLs to kill autologous tumor cells was significantly different(P

AIM: To study effects of tumour necrosis factor alpha(TNF?) and interleukin-10(IL-10) on human cytomegalovirus AD169 (HCMV AD169) infection in human embryonic lung fibroblasts (HEL),and the ability of the infected HEL to produce TNF?. We have attempted to understand the effect of cytokines in the immune of HCMV infection. METHODS: TNF??IL-10 were added separately with different concentrations before 24 h HCMV infection of HEL to study the effect of TNF? and IL-10 on multiplication of HCMV. HCMV was incubated with HEL, TNF? in culture supernatants were measured at 4, 24, 48, 72, 96 h postinfection. The level of TNF? was measured by enzyme-linked immunosorbent assay( ELISA). RESULTS: The addition of TNF? with the concentration of 10-100 ?g/L or IL-10 with the concentration of 1-10 ?g/L before 24 h HCMV infection of HEL could remarkably inhibited the multiplication of HCMV in HEL. Level of TNF? didn't increase in infected cell supernatants. CONCLUSION: TNF? and IL-10 play an important role in the immune of HCMV infection.

AimTo study the effect of interferon gamma( IFN-γ) and tumor necrosis factor alpha(TNF-α) in the immune pathogenesis of dengue virus infection. Method The serum levels of IFN-γ and TNF-α were measured with emzyme linked immunosorbent assay (ELISA) method in 30 cases of the patients with the dengue virus infection in Guangzhou district. The results were treated with t-test of two sample mean. ResultsThe serum levels of IFN-γ and TNF-α in patients with the dengue virus infection were much higher than healthy controls( P ＜ 0.05、 P ＜ 0.01 ). IFN-γ was detectable on the first day of postinfection. Level of IFN-γ reached their peaks on the second day, then declined . The level of TNF-α had an obvious rise from the second day and reached their peaks on the third day, then declined. ConclusionThe data suggest that the IFN-γ and TNF-α may play an important role in the dengue virus pathogenicity and immunity.

Objective To study the changes of tissue plasminogen activator (t-PA), plasminogen activator inhibitor 1 (PAI-1), and soluble thrombomodulin (sTM) induced by dengue 2 virus (D 2V) infection of vascular endothelial cells. Methods The effects of D 2V infection on the production of t-PA, PAI-1, and sTM of human umbilical cord vein cells were studied. Results D 2V infection significantly induced the secretion of sTM and t-PA but showed no such effects on PAI-1 of human endothelial cells. Antibody against IL-6 inhibited D 2V-induced t-PA production of endothelial cells. A close correlation between serum levels of IL-6 and t-PA was found in dengue hemorrhagic fever (DHF) but not in dengue fever (DF) patients. Conclusion IL-6 can regulate D 2V-induced t-PA production of endothelial cells, suggesting that endothelial cells can be the target for D 2V infection and that D 2V-induced t-PA, TM, and IL-6 production of endothelial cells may contribute to the pathogenic development of dengue haemorrhagic fever/dengue shock syndrome (DHF/DSS).

AIM: The aim of this study is to elucidate the effects of lipopolysaccharide (LPS) on tissue plasminogen activator(tPA) and plasminogen activator inhibitor type-1(PAI-1) expression and secretion in endothelial cells. METHODS: Cultured human umbilical vein endothelial cells (HUVECs) were induced by LPS for different times. Cell viability was then determined by cell counting kit-8. tPA and PAI-1 activities in the media were assayed by fibrin overlay and reverse fibrin autograph, respectively. Cytoplasmic RNA was prepared using the Trizol method and was assayed for PAI-I and tPA mRNA levels by reverse transcript-polymerase chain reaction(RT-PCR). RESULTS: LPS(10 mg/L) did not produce cell toxicity according to LDH determination in culture media. PAI-1 activity in LPS group was high (P0.05). CONCLUSION: LPS (10 mg/L) did not show signs of cell toxicity, but promoted the expression of PAI-1 mRNA and induced an increase activity of PAI-1. However, LPS (10 mg/L) did not change tPA mRNA expression. The time-dependent increase in PAI-1 mRNA expression and activity shifts the local balance toword increased anti-fibrinolytic capacity, which can amplify the extent of acute thrombosis after plaque rupture. This is one of the possible reasons that cause thrombus,blood coagulation and disseminated intravascular coagulation (DIC) during septicemia.

Objective To investigate the effects of microRNA-17-92 on radiosensitivity of human mantle cell lymphoma cells. Methods Tetracycline-regulated pRevTet-On expression system was established to generate cell line Z138c-miR-17-92 with over-expressed miR-17-92 and cell line Z138c-TMP2. Cell proliferation was measured by 3 H-TdR incorporation and viable cell counting stained with typan blue. Cell cycle distribution was analysed by flow cytometry(FCM). Results More viable and proliferous cells were counted in group miR-17-92,when exposure dose was greater than 2 Gy and incubation time was longer than 48 h under the same condition (t = -3. 12 and -3.28,P ＜0. 05). The percentage of G2/M cells in group TMP2 was increased while no obvious cell cycle arrests were found in group miR-17-92 at 2 and 4 Gy (t = 2. 885, P ＜ 0.05 ). When cells were incubated for 96 h, higher percentage of propidium iodide (PI) positively stained cells were found in group TMP2 (24. 02% vs. 36. 16% )compared with group miR-17-92 (6.49% vs. 11.39% ) at 2 and 4 Gy, respectively( t = - 17.59, - 4. 972, P ＜ 0.05 ).Conclusions Overexpression of microRNA-17-92 decreased the radiosensitivity of human mantle cell lymphoma cells by inhibition of cell cycle changes and cell apoptosis.

Objective To investigate the effect of cimetidine on the clonal expansion of TCR V? subfamily of T cells in cord blood after the stimulation by K562 cells in vitro.Methods Cimetidine(1?10-5 mol/L) or K562 cells(1?106/ml) or both of them were respectively cultured with mononuclear cells(MNC) isolated from normal human cord blood for 2 weeks.After the induction,specific cytotoxicity of the proliferated T cells were detected with K562 cells as the target cells.The selective usages and clonal expansion of TCR V? subfa-mily of T cells were analyzed by RT-PCR and genescan technique.Results After induction for 2 weeks,the 3 groups showed the increased cell proliferation,in which specific cytotoxicity of T cells induced by both cimetidine and K562 cells against K562 cells was enhanced significantly compared with the other 2 groups(P